1. Field of the Invention
The present general inventive concept relates to a hard disk drive (HDD), and more particularly, to a HDD which includes a simple structure to be made light and is capable of reducing a magnetic leakage flux which affects a voice coil motor (VCM).
2. Description of the Related Art
Hard disk drives (HDDs) write data on and/or read data from disks using read and/or write heads. Since the HDDs are also capable of accessing mass data at a high speed, they are widely used as secondary memory units, etc., of computer systems.
Such HDDs have had high capacities and have expanded their applications due to the realization of high Tracks Per Inch (TPI) and Bits Per Inch (BTI).
Therefore, there have been briskly developed small HDDs which are to be used in portable electronic products, including notebook computers, personal digital assistants (PDAs), portable phones, etc. 2.5-inch HDDs have been developed and used in notebook computers, etc. Additionally, 0.85-inch HDDs having sizes similar to the size of coins have been briskly studied and developed. Such 0.85-inch HDDS have been used or are expected to be used in portable phones, MEPG Audio Layer-3s (MP3s), or the like.
Such a HDD includes a plurality of parts related to reading and writing of information, e.g., a disk, a base on which a head stack assembly (HSA) having a voice coil motor (VCM), etc., are installed, and a cover which is combined with an upper surface of the base.
In the case of a small form factor HDD (SFF HDD) having a diameter of 1.8 inch or less, a cover is mainly formed of a SPCE (Cold Rolled Steel) or steel use stainless (SUS). In this case, the cover may be easily pressed and have a rigidity in contradistinction to thickness. In particular, the cover may greatly reduce a leakage of a magnetic flux which affects the VCM.
However, if the cover is formed of the SPCE (Cold Rolled Steel), the cover is heavier than when it is formed of a nonferrous material. This does not satisfy an object of the SFF HDD to be made light in weight.
Accordingly, there may be considered a method of forming a cover of a nonferrous material instead of a SPCE (Cold Rolled Steel) in order to reduce a weight of the cover. However, if the cover is formed of the nonferrous material only to reduce the weight, a magnetic leakage flux may greatly affect a VCM of the SFF HDD. Therefore, the cover should be improved such that a structure thereof meets requirements of an SFF HDD to reduce the magnetic leakage flux affecting the VCM and to be made light in weight.